Hi,
I have a small block Ford and it's sometimes a problem getting all the air out of the system when filling it. You have to burp the air out. Some guys fill it then run the engine with the radiator cap off, wait 'til the thermostat opens and then rev the engine a bit to evacuate the air through the radiator cap. This method can be messy.
I installed a burp valve with a small piece of pipe into the intake manifold, where the heater hose fitting would go. I am not running a heater so I was able to use the manifold heater hose port. I installed a small length of pipe, then used an elbow and attached a brass drain or pet cock fitting. When I fill the system I keep the drain cock open allowing the air to escape.
I attached a picture of the burp valve I installed, just behind the thermostat housing and next to the distributor.
Tony
